The present invention relates to a printer that is used with oversized printable sheets, such as a poster, foam backboard or similar materials that are large, and are preferred to be on boards that are not bent or easily driven through rolls. The printer is mounted onto a frame that is driven independently over and along the surface of the printing substrate, such as a tag board or the like, while the board remains stationary. The printer is preferably an ink jet printer, that is synchronized with a forward drive for the printer.
At the present time, printing posters has been a difficult task because the posters are large, and most printers do not accommodate wide substrates or papers and, also, most printers do not provide for feeding a flat substrate through the printer. Printers that are developed for large substrates are very expensive, and thus are not readily used by people that are making posters.
The present invention relates to a printer for printing large area sheets of print media or substrates, such as posters, where the print media remains on a flat support and the printhead is driven on a standard printer head across the surface as it prints. The print media or substrate remains stationary, and can be supported on a suitable table, and once the printer frame and printhead is oriented at a home position and the print media is also positioned at a reference or home position, the frame will move across the print media substrate uniformly to provide for transverse movement of the printer for printing the images (such as a poster or graphic print) under a printer control.
Standard printheads can be used, as shown an ink jet printer, but the support or frame for the printhead is elongated to accommodate the width of the print media sheet that is desired.
The print media sheet can be supported on any planar surface, and can be positioned so that the print media sheet will have one traverse edge at a known location or start position, while the printer is positioned in a home position relative to the known or start edge of the print media sheet so that the printer frame is square with the longitudinal edges of the substrate.
Once the print media sheet and the printer are properly aligned, the printer is started. The printhead is driven transversely along the printer frame as is now done, and the frame is also driven longitudinally along the sheet with a variable speed DC motor, or a stepper motor. The printer moves along the longitudinal length of the sheet which is the travel direction axis of the printer. The travel direction is perpendicular to the movement of the printhead along the printer frame. The printhead moves laterally across the print media sheet at each step or increment of movement of the printer frame as it is driven along the longitudinal length to complete the printing for that particular line, in a normal manner. The printer frame is incrementally driven along the entire length of the sheet to complete the print job.
Standard printheads and printhead drives can be utilized, and the printhead support frame is extended in length to the desired length for the width of the sheet to be printed. Poster boards that are in the range of 22-24xe2x80x3 in width, plus any desired length, can be printed. Wider widths can be printed as well, with the frames modified for adequate support along the wider widths. The print media sheet can be any thickness desired for posters or the like, and the printer easily accommodates foam backed poster boards.
The drive for moving the printer frame can be made as desired, but high friction material rollers are shown and are utilized for driving against the printing surface. The rollers should be non-marking. The program control for the printing program can be a program in a personal computer or other computer operating in a known manner. The printer can be guided on side rails that support the printer and driven along the rails or it can be supported on the rails and driven as shown.